CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Foreign currency translation adjustment, tax expense (benefit)	$ 136	$ (4)	$ (44)

Amount of tax effect, net of reclassification adjustments, on the result from the process of expressing in the reporting currency of the reporting entity those amounts that are denominated or measured in a different currency, attributable to the parent entity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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-URI http://asc.fasb.org/extlink&oid=7656940&loc=SL4569643-111683

+ Details